A solid cube of mass 5 kg is placed on a rough horizontal surface, in xy-
plane as shown. The friction coefficient between the surface and the
cube is 0.4. An external force = 6 + 8 + 20 N is applied on the cube.
(use g = 10 m/)
(A) The block starts slipping over the surface
(B) The friction force on the cube by the surface is 10 N.
(C) The friction force acts in xy-plane at angle 12 with the positive
x-axis in clockwise direction.
(D) The contact force exerted by the surface on the cube is 10N.